RESUMO
Mu-opioid receptors (MORs) in the amygdala and striatum are important in addictive and rewarding behaviors. Foxp2 is a marker of intercalated (ITC) cells in the amygdala and a subset of striatal medium spiny neurons (MSNs), both of which express MORs in wild-type mice. For the current series of studies, we characterized the behavior of mice with genetic deletion of the MOR gene Oprm1 in Foxp2-expressing neurons (Foxp2-Cre/Oprm1 fl/fl ). Male and female Foxp2-Cre/Oprm1 fl/fl mice were generated and heterozygous Cre+ (knockout) and homozygous Cre-(control) animals were tested for aversion-resistant alcohol consumption using an intermittent access (IA) task, operant responding for a sucrose reward, conditioned place aversion (CPA) to morphine withdrawal, and locomotor sensitization to morphine. In IA, mice with the MOR-knockout were more sensitive to quinine-adulterated ethanol (EtOH) and less aversion-resistant, as they decreased EtOH consumption from baseline at all quinine concentrations, while control animals did not. In operant conditioning, Cre+ mice similarly exhibited less aversion-resistant reward seeking than Cre-mice when sucrose was adulterated with quinine. For CPA, both control and MOR-knockout mice demonstrated withdrawal-induced aversion. For locomotor sensitization, Cre+ mice demonstrated decreased locomotion following morphine injection compared to Cre-mice. The results of these studies suggest that MOR expression on Foxp2-expressing neurons is not necessary for rewarded behaviors or expression of opioid withdrawal but may be involved in aversion-resistance.
RESUMO
Implementation of high-fidelity 2-qubit operations is a key ingredient for scalable quantum error correction. In superconducting qubit architectures, tunable buses have been explored as a means to higher-fidelity gates. However, these buses introduce new pathways for leakage. Here we present a modified tunable bus architecture appropriate for fixed-frequency qubits in which the adiabaticity restrictions on gate speed are reduced. We characterize this coupler on a range of 2-qubit devices, achieving a maximum gate fidelity of 99.85%. We further show the calibration is stable over one day.
RESUMO
BACKGROUND: A freshly deceased mud crab (Scylla serrata) exhibiting multiple white spots under the carapace was found in Pumicestone Passage, northern Moreton Bay in May 2018. This crab was taken from within a biosecurity zone established due to a recent incursion of White Spot Syndrome Virus (WSSV) into populations of wild penaeids (Penaeus spp., Metapenaeus spp.) and crabs (Thalamita crenata) in the area. Because grossly visible white spots have been previously observed under the carapace of moribund S. serrata with white spot disease (WSD) in India, an investigation into the cause of death was undertaken. CASE REPORT: The affected S. serrata was negative for WSSV DNA when gill samples were tested by real-time PCR. Histopathology found no evidence of WSD lesions in the form of basophilic hypertrophied intranuclear inclusions in any tissues of ectodermal or mesodermal origin. Histopathology of the affected carapace showed that the white spots consisted of multiple lighter coloured foci in the exocuticle formed from concentric crystalline-like rings, which extended into the endocuticle. These were interpreted as evidence of mineral mobilisation within the carapace during the pre-moult (D1 or D2) stage of the moult cycle. The cause of death in this case therefore may have been due to moult-related complications. CONCLUSION: These observations confirm that formation of grossly visible white spots under the carapace of S. serrata are not pathognomonic for infection with WSSV. Similar observations in previous studies where WSSV was detected by PCR in this same host may have been incidental findings.
Assuntos
Braquiúros , Vírus da Síndrome da Mancha Branca 1 , Exoesqueleto , Animais , Austrália , Baías , ÍndiaRESUMO
White spot disease, caused by infection with white spot syndrome virus (WSSV), is a serious panzootic affecting prawn aquaculture. The disease has spread rapidly around the prawn-culturing regions of the world through a number of previously identified mechanisms. The ability to distinguish and trace strains of WSSV is of great benefit to identify, and then limit, the translocation routes of the disease. Here, we describe a novel genotyping method using 34 short tandem repeat regions of the viral genome concurrently. This technique is highly sensitive to strain differences when compared to previous methods. The efficacy of the described method is demonstrated by testing WSSV isolates from around the globe, showing regional genotypic differences. The differences in the genotypes were used to create a global minimum spanning network, and in most cases the observed relationships were substantiated with verification of transboundary movement. This novel panel of STR markers will provide a valuable epidemiological tool for white spot disease. We have applied this to an outbreak of the disease in Queensland, Australia, that occurred in 2016. While the results indicate that the source of this outbreak currently remains cryptic, the analyses have provided valuable insights with which to further study the origins of the strains involved.
Assuntos
Técnicas de Genotipagem/métodos , Vírus da Síndrome da Mancha Branca 1/genética , Animais , Aquicultura , Austrália , Surtos de Doenças , Genoma Viral/genética , Genótipo , Repetições de Microssatélites/genética , Penaeidae/virologiaRESUMO
Ring resonators provide a means of filtering specific wavelengths from a waveguide, and optionally dropping the filtered wavelengths into a second waveguide. Both of these features are potentially useful for astronomical instruments. In this paper we focus on their use as notch filters to remove the signal from atmospheric OH emission lines from astronomical spectra. We derive the design requirements for ring resonators for OH suppression from theory and finite difference time domain simulations. We find that rings with small radii (< 10 µm) are required to provide an adequate free spectral range, leading to high index contrast materials such as Si and Si3N4. Critically coupled rings with high self-coupling coefficients should provide the necessary Q factors, suppression depth, and throughput for efficient OH suppression, but will require post-inscription tuning of the coupling and the resonant wavelengths. The overall prospects for the use of ring resonators in astronomical instruments is promising, provided efficient fibre-chip coupling can be achieved.
RESUMO
Like a quantum computer designed for a particular class of problems, a quantum simulator enables quantitative modelling of quantum systems that is computationally intractable with a classical computer. Superconducting circuits have recently been investigated as an alternative system in which microwave photons confined to a lattice of coupled resonators act as the particles under study, with qubits coupled to the resonators producing effective photon-photon interactions. Such a system promises insight into the non-equilibrium physics of interacting bosons, but new tools are needed to understand this complex behaviour. Here we demonstrate the operation of a scanning transmon qubit and propose its use as a local probe of photon number within a superconducting resonator lattice. We map the coupling strength of the qubit to a resonator on a separate chip and show that the system reaches the strong coupling regime over a wide scanning area.
RESUMO
AIM: This study compared the efficacy and patient acceptability of two methods of bowel preparation for flexible sigmoidoscopy. METHODS: Patients attending for outpatient flexible sigmoidoscopy were prospectively randomized to receive one Fleet ready-to-use enema or 2 x 4 g glycerin suppositories, 2 h preprocedure. Patient and endoscopist questionnaires were used to compare the outcomes. RESULTS: From November 2000 to August 2001, 203 (male = 95; female = 108) patients were randomized. Patient data available for 163 patients (enema = 93; suppository = 70) revealed: ease of use (enema = 52; suppository = 25; P < 0.02, Fisher's exact); assistance required (enema = 19; suppository = 3; P < 0.005, Fisher's exact); grade of effectiveness (enema = 83; suppository = 44; P < 0.0001, Fisher's exact), and whether patients wished to try another preparation in future (enema = 16; suppository = 24; P = 0.016, Fisher's exact). Endoscopist data available for 151 patients (enema = 76; suppository = 75) revealed: average depth of insertion (enema = 53.6 +/- 11.6 cm; suppository 46.3 +/- 13.7 cm; P < 0.001, Student's t test); acceptable (excellent + good) quality of preparation [enema = 60 (78.9%); suppository = 34 (45.3%); P < 0.0001, Fisher's exact]. CONCLUSION: Bowel preparation for flexible sigmoidoscopy using a single Fleet enema is acceptable to patients and more effective than glycerin suppositories.
Assuntos
Catárticos , Glicerol/uso terapêutico , Satisfação do Paciente , Fosfatos/uso terapêutico , Sigmoidoscopia/métodos , Supositórios/uso terapêutico , Feminino , Glicerol/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Aceitação pelo Paciente de Cuidados de Saúde , Fosfatos/administração & dosagem , Estudos Prospectivos , Método Simples-Cego , Solventes/administração & dosagem , Solventes/uso terapêutico , Supositórios/administração & dosagem , Inquéritos e QuestionáriosRESUMO
The analyzing power for proton-carbon elastic scattering in the Coulomb-nuclear interference region of momentum transfer, 9.0x10(-3)<-t<4.1x10(-2) (GeV/c)(2), was measured with a 21.7 GeV/c polarized proton beam at the Alternating Gradient Synchrotron of Brookhaven National Laboratory. The ratio of hadronic spin-flip to nonflip amplitude, r(5), was obtained from the analyzing power to be Rer(5)=0.088+/-0.058 and Imr(5)=-0.161+/-0.226.
RESUMO
The binding of tumor necrosis factor alpha (TNF-alpha) to the type-1 TNF receptor (TNFRc1) plays an important role in inflammation. Despite the clinical success of biologics (antibodies, soluble receptors) for treating TNF-based autoimmune conditions, no potent small molecule antagonists have been developed. Our screening of chemical libraries revealed that N-alkyl 5-arylidene-2-thioxo-1,3-thiazolidin-4-ones were antagonists of this protein-protein interaction. After chemical optimization, we discovered IW927, which potently disrupted the binding of TNF-alpha to TNFRc1 (IC(50) = 50 nM) and also blocked TNF-stimulated phosphorylation of Ikappa-B in Ramos cells (IC(50) = 600 nM). This compound did not bind detectably to the related cytokine receptors TNFRc2 or CD40, and did not display any cytotoxicity at concentrations as high as 100 microM. Detailed evaluation of this and related molecules revealed that compounds in this class are "photochemically enhanced" inhibitors, in that they bind reversibly to the TNFRc1 with weak affinity (ca. 40-100 microM) and then covalently modify the receptor via a photochemical reaction. We obtained a crystal structure of IV703 (a close analog of IW927) bound to the TNFRc1. This structure clearly revealed that one of the aromatic rings of the inhibitor was covalently linked to the receptor through the main-chain nitrogen of Ala-62, a residue that has already been implicated in the binding of TNF-alpha to the TNFRc1. When combined with the fact that our inhibitors are reversible binders in light-excluded conditions, the results of the crystallography provide the basis for the rational design of nonphotoreactive inhibitors of the TNF-alpha-TNFRc1 interaction.
Assuntos
Morfolinas/química , Receptores do Fator de Necrose Tumoral/antagonistas & inibidores , Fator de Necrose Tumoral alfa/metabolismo , Antígenos CD/química , Antígenos CD/metabolismo , Cristalografia por Raios X , Humanos , Modelos Moleculares , Estrutura Molecular , Fotoquímica , Receptores do Fator de Necrose Tumoral/química , Receptores do Fator de Necrose Tumoral/metabolismo , Receptores Tipo I de Fatores de Necrose Tumoral , Proteínas Recombinantes/antagonistas & inibidores , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismoRESUMO
The anaphylatoxin C3a is a potent chemotactic peptide and inflammatory mediator released during complement activation which binds to and activates a G-protein-coupled receptor. Molecular cloning of the C3aR has facilitated studies to identify nonpeptide antagonists of the C3aR. A chemical lead that selectively inhibited the C3aR in a high throughput screen was identified and chemically optimized. The resulting antagonist, N(2)-[(2,2-diphenylethoxy)acetyl]-L-arginine (SB 290157), functioned as a competitive antagonist of (125)I-C3a radioligand binding to rat basophilic leukemia (RBL)-2H3 cells expressing the human C3aR (RBL-C3aR), with an IC(50) of 200 nM. SB 290157 was a functional antagonist, blocking C3a-induced C3aR internalization in a concentration-dependent manner and C3a-induced Ca(2+) mobilization in RBL-C3aR cells and human neutrophils with IC(50)s of 27.7 and 28 nM, respectively. SB 290157 was selective for the C3aR in that it did not antagonize the C5aR or six other chemotactic G protein-coupled receptors. Functional antagonism was not solely limited to the human C3aR; SB 290157 also inhibited C3a-induced Ca(2+) mobilization of RBL-2H3 cells expressing the mouse and guinea pig C3aRS: It potently inhibited C3a-mediated ATP release from guinea pig platelets and inhibited C3a-induced potentiation of the contractile response to field stimulation of perfused rat caudal artery. Furthermore, in animal models, SB 290157, inhibited neutrophil recruitment in a guinea pig LPS-induced airway neutrophilia model and decreased paw edema in a rat adjuvant-induced arthritis model. This selective antagonist may be useful to define the physiological and pathophysiological roles of the C3aR.
Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Arginina/farmacologia , Compostos Benzidrílicos/farmacologia , Complemento C3a/metabolismo , Proteínas Inativadoras do Complemento/farmacologia , Proteínas de Membrana , Receptores de Complemento/antagonistas & inibidores , Animais , Anti-Inflamatórios não Esteroides/metabolismo , Anti-Inflamatórios não Esteroides/farmacocinética , Arginina/análogos & derivados , Arginina/metabolismo , Arginina/farmacocinética , Artrite Experimental/imunologia , Artrite Experimental/patologia , Compostos Benzidrílicos/metabolismo , Compostos Benzidrílicos/farmacocinética , Ligação Competitiva , Linhagem Celular , Proteínas Inativadoras do Complemento/metabolismo , Proteínas Inativadoras do Complemento/farmacocinética , Modelos Animais de Doenças , Edema/patologia , Edema/prevenção & controle , Cobaias , Membro Posterior , Humanos , Injeções Intraperitoneais , Leucocitose/imunologia , Leucocitose/patologia , Masculino , Camundongos , Contração Muscular/efeitos dos fármacos , Infiltração de Neutrófilos/efeitos dos fármacos , Ratos , Ratos Endogâmicos Lew , Ratos Sprague-Dawley , Receptores de Complemento/metabolismo , Células Tumorais CultivadasRESUMO
An academic 12-lead electrocardiogram (ECG) core laboratory aims to provide the highest possible quality ECG recording, measurement, and storage to aid clinicians in research into important cardiovascular outcomes and to maximize the credibility of scientific results based solely, or in part, on ECG data. This position paper presents a guide for the structure and function of an academic ECG core laboratory. The key functional aspects are: 1) Data collection, 2) Staff composition, 3) Diagnostic measurement and definition standards, 4) Data management, 5) Academic considerations, 6) Economic consideration, and 7) Accreditation. An ECG Core Laboratory has the responsibility for rapid and accurate analysis and responsible management of the electrocardiographic data in multicenter clinical trials. Academic Laboratories, in addition, provide leadership in research protocol generation and production of research manuscripts for submission to the appropriate peer-review journals.
Assuntos
Eletrocardiografia/normas , Laboratórios Hospitalares/normas , Acreditação , Humanos , Projetos de PesquisaRESUMO
The effects of a second generation p38 mitogen-activated protein kinase (MAPK) inhibitor, SB 239063 [trans-1-(4-hydroxycyclohexyl)-4-(4-fluorophenyl)-5-(2-methoxypyridim idi n-4-yl)imidazole; IC(50) = 44 nM vs. p38 alpha], were assessed in models that represent different pathological aspects of chronic obstructive pulmonary disease (COPD) [airway neutrophilia, enhanced cytokine formation and increased matrix metalloproteinase (MMP)-9 activity] and in a model of lung fibrosis. Airway neutrophil infiltration and interleukin (IL)-6 levels, assessed by bronchoalveolar lavage 48 h after lipopolysaccharide (LPS) inhalation, were inhibited dose dependently by 3-30 mg/kg of SB 239063 given orally twice a day. In addition, SB 239063 (30 mg/kg orally) attenuated IL-6 bronchoalveolar lavage fluid concentrations (>90% inhibition) and MMP-9 activity (64% inhibition) assessed 6 h after LPS exposure. In guinea pig cultured alveolar macrophages, SB 239063 inhibited LPS-induced IL-6 production (IC(50) of 362 nM). In a bleomycin-induced pulmonary fibrosis model in rats, treatment with SB 239063 (2.4 or 4.8 mg/day via osmotic pump) significantly inhibited bleomycin-induced right ventricular hypertrophy (indicative of secondary pulmonary hypertension) and increases in lung hydroxyproline synthesis (indicative of collagen synthesis and fibrosis). Therefore, SB 239063 demonstrates activity against a range of sequelae commonly associated with COPD and fibrosis, supporting the therapeutic potential of p38 MAPK inhibitors such as SB 239063 in chronic airway disease.
Assuntos
Citocinas/biossíntese , Inibidores Enzimáticos/farmacologia , Imidazóis/farmacologia , Lipopolissacarídeos/toxicidade , Pneumopatias Obstrutivas/fisiopatologia , Metaloproteinase 9 da Matriz/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Neutrófilos/fisiologia , Fibrose Pulmonar/prevenção & controle , Pirimidinas/farmacologia , Animais , Bleomicina/toxicidade , Células Cultivadas , Citocinas/sangue , Modelos Animais de Doenças , Cobaias , Humanos , Hipertensão Pulmonar/induzido quimicamente , Hipertensão Pulmonar/prevenção & controle , Inflamação/fisiopatologia , Inflamação/prevenção & controle , Proteína Antagonista do Receptor de Interleucina 1 , Interleucina-1/sangue , Interleucina-6/sangue , Interleucina-8/sangue , Pulmão/efeitos dos fármacos , Pulmão/fisiopatologia , Masculino , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Neutrófilos/efeitos dos fármacos , Alvéolos Pulmonares/efeitos dos fármacos , Alvéolos Pulmonares/imunologia , Fibrose Pulmonar/induzido quimicamente , Ratos , Ratos Endogâmicos Lew , Sialoglicoproteínas/sangue , Fator de Necrose Tumoral alfa/metabolismo , Proteínas Quinases p38 Ativadas por MitógenoAssuntos
Glucosídeos/síntese química , Antagonistas dos Receptores de Neurocinina-1 , Receptores de Somatostatina/antagonistas & inibidores , Somatostatina/química , Substância P/antagonistas & inibidores , Animais , Células CHO , Células COS , Cricetinae , Glucosídeos/química , Glucosídeos/metabolismo , Glucosídeos/farmacologia , Humanos , Proteínas de Membrana , Mimetismo Molecular , Receptores da Neurocinina-1/metabolismo , Receptores de Somatostatina/agonistas , Receptores de Somatostatina/metabolismo , Somatostatina/agonistasRESUMO
The cardiopulmonary profile of three rat strains (Sprague-Dawley, Wistar and High altitude-sensitive) was compared upon exposure to hypoxia (9% O2) for 0, 7 or 14 days. No differences were observed among the in vitro contractile (ET-1) and relaxant (carbachol) responses of pulmonary artery isolated from the three strains during normoxia. Chronic hypoxia decreased ET-1 contractile responses and diminished relaxant responses to carbachol similarly in all strains. In Sprague-Dawley, Wistar and High altitude-sensitive rats, pulmonary arterial pressure rose time-dependently and was elevated by 108%, 116% and 167%, respectively, after 14 days of hypoxia compared to normoxic controls. Right ventricular hypertrophy was increased by 51%, 93% and 55%, respectively, at 14 days. Hypoxia-induced hypertrophy and medial thickening in the pulmonary vasculature were more pronounced in High altitude-sensitive rats. Sprague-Dawley exhibited hypoxia-induced airway hyperresponsiveness to intravenous methacholine, but there were no hypoxia- or strain-related differences in in vitro tracheal contractility. Although each strain exhibited greater sensitivity for a particular hypoxia-induced parameter, pulmonary vascular functional and structural changes suggest that High altitude-sensitive rats represent a choice model of hypoxia-induced pulmonary hypertension.
Assuntos
Hipóxia/fisiopatologia , Artéria Pulmonar/fisiopatologia , Altitude , Animais , Carbacol/farmacologia , Modelos Animais de Doenças , Endotelina-1/farmacologia , Endotelinas/sangue , Hipertensão Pulmonar/etiologia , Hipertensão Pulmonar/patologia , Hipertensão Pulmonar/fisiopatologia , Hipertrofia , Hipertrofia Ventricular Direita/etiologia , Hipóxia/patologia , Técnicas In Vitro , Masculino , Cloreto de Metacolina/farmacologia , Artéria Pulmonar/patologia , Ratos , Ratos Sprague-Dawley , Ratos Wistar , Especificidade da Espécie , Traqueia/efeitos dos fármacos , Traqueia/fisiopatologia , Vasoconstrição/efeitos dos fármacos , Vasodilatação/efeitos dos fármacosRESUMO
BACKGROUND: Recent studies have reported that negative T waves in the setting of acute coronary events are associated with Thrombolysis In Myocardial Infarction flow grade 3 in the infarct-related artery and with improved parameters of ventricular function rather than with ischemia. METHODS: Patients enrolled in the Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries (GUSTO-I) angiographic substudy (ie, patients with acute infarction randomly assigned to one of 4 thrombolytic regimens who then underwent coronary angiography) were included in this study if they survived at least 24 hours and had no confounding electrocardiographic factors (n = 1505). RESULTS: More patients had negative T waves develop (NT group, n = 938 [62%]) than not (PT group, n = 567 [38%]). Peak creatine kinase MB, time to thrombolysis, and randomization to accelerated alteplase were no different between the groups. Thirty days after admission, 12 patients in the NT group had died versus 25 patients in the PT group (1.3% vs. 4.4%; P <.001; odds ratio for negative T waves 0.28; 95% confidence interval 0.14-0.56). The difference persisted when only patients who survived at least 3 days were analyzed. After adjusting for relevant covariates (including presence of new Q waves in the follow-up electrocardiogram), negative T waves were an independent predictor for survival (P =. 007; odds ratio for negative T waves 0.38; 95% confidence interval 0. 18-0.78). Patients in the NT group were 35% more likely to have achieved patency of the infarct-related artery, although this difference was not statistically significant. CONCLUSIONS: Negative T waves shortly after acute myocardial infarction treated with thrombolysis were markers for improved 30-day survival rate. This finding merits prospective testing.
Assuntos
Eletrocardiografia/classificação , Fibrinolíticos/uso terapêutico , Infarto do Miocárdio/diagnóstico , Adulto , Idoso , Biomarcadores/análise , Angiografia Coronária , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/mortalidade , Prognóstico , Estudos Prospectivos , Sensibilidade e Especificidade , Taxa de SobrevidaRESUMO
Since the discovery of p38 MAP kinase in 1994, our understanding of its biology has progressed dramatically. The key advances include (1) identification of p38 MAP kinase homologs and protein kinases that act upstream and downstream from p38 MAP kinase, (2) identification of interesting and potentially important substrates, (3) elucidation of the role of p38 MAP kinase in cellular processes and (4) the establishment of the mechanism by which the pyridinylimidazole p38 MAP kinase inhibitors inhibit enzyme activity. It is now known that there are four members of the p38 MAP kinase family. They differ in their tissue distribution, regulation of kinase activation and subsequent phosphorylation of downstream substrates. They also differ in terms of their sensitivities toward the p38 MAP kinase inhibitors. The best-studied isoform is p38 alpha, whose activation has been observed in many hematopoietic and non-hematopoietic cell types upon treatment with appropriate stimuli. The pyridinylimidazole compounds, exemplified by SB 203580, were originally prepared as inflammatory cytokine synthesis inhibitors that subsequently were found to be selective inhibitors of p38 MAP kinase. SB 203580 inhibits the catalytic activity of p38 MAP kinase by competitive binding in the ATP pocket. X-ray crystallographic studies of the target enzyme complexed with inhibitor reinforce the observations made from site-directed mutagenesis studies, thereby providing a molecular basis for understanding the kinase selectivity of these inhibitors. The p38 MAP kinase inhibitors are efficacious in several disease models, including inflammation, arthritis and other joint diseases, septic shock, and myocardial injury. In all cases, p38 activation in key cell types correlated with disease initiation and progression. Treatment with p38 MAP kinase inhibitors attenuated both p38 activation and disease severity. Structurally diverse p38 MAP kinase inhibitors have been tested extensively in preclinical studies.
Assuntos
Citocinas/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Animais , Citocinas/fisiologia , Inibidores Enzimáticos/uso terapêutico , Humanos , Imidazóis/farmacologia , Imidazóis/uso terapêutico , Sistema de Sinalização das MAP Quinases/fisiologia , Proteínas Quinases Ativadas por Mitógeno/fisiologia , Especificidade por Substrato , Tiazóis/farmacologia , Tiazóis/uso terapêutico , Proteínas Quinases p38 Ativadas por MitógenoRESUMO
The anti-inflammatory/antiallergic activity of a novel second-generation p38 mitogen-activated protein kinase inhibitor, SB 239063[trans-1-(4-hydroxycyclohexyl) -4-(4-fluorophenyl)-5-(2-methoxypyridimidin-4-yl)imidazole], was investigated in vivo and in vitro. SB 239063 had an IC(50) of 44 nM for inhibition of recombinant purified human p38alpha. In lipopolysaccharide-stimulated human peripheral blood monocytes, SB 239063 inhibited interleukin-1 and tumor necrosis factor-alpha production (IC(50) values = 0.12 and 0.35 microM, respectively). A role for p38 kinase in cytokine-associated inflammation in the mouse was shown by p38 activation in the lung and inhibition of lipopolysaccharide-induced tumor necrosis factor-alpha production by SB 239063 (ED(50) = 5.8 mg/kg p.o.). Antiallergic activity was demonstrated by essential abolition (approximately 93% inhibition) of inhaled ovalbumin (OA)-induced airway eosinophilia by SB 239063 (12 mg/kg p.o.), measured by bronchoalveolar lavage (BAL) in OA-sensitized mice. In addition, p38 kinase was found by Western analysis to be activated in guinea pig lung. Administration of SB 239063 (10 or 30 mg/kg p.o.) in conscious guinea pigs markedly reduced ( approximately 50% inhibition) OA-induced pulmonary eosinophil influx, measured by BAL 24 h after antigen. SB 239063 (10 mg/kg b.i.d. p.o.) administered after leukotriene D(4) inhalation, reduced by 60% the persistent airway eosinophilia seen at 4 days. Apoptosis of cultured eosinophils isolated from guinea pig BAL was increased by SB 239063 (1-10 microM) in the presence of interleukin-5. These results indicate that SB 239063 is a potent inhibitor of inflammatory cytokine production, inhibits eosinophil recruitment, in addition to enhancing apoptosis of these cells. Collectively, the results support the potential utility of p38 kinase inhibitors, such as SB 239063, for the treatment of asthma and other inflammatory disorders.
Assuntos
Proteínas Quinases Dependentes de Cálcio-Calmodulina/antagonistas & inibidores , Citocinas/biossíntese , Inibidores Enzimáticos/farmacologia , Eosinofilia/induzido quimicamente , Imidazóis/farmacologia , Proteínas Quinases Ativadas por Mitógeno , Pirimidinas/farmacologia , Sistema Respiratório/patologia , Administração por Inalação , Animais , Apoptose/efeitos dos fármacos , Western Blotting , Líquido da Lavagem Broncoalveolar/citologia , Broncoconstrição/efeitos dos fármacos , Eosinofilia/patologia , Cobaias , Humanos , Leucotrieno D4/administração & dosagem , Leucotrieno D4/farmacologia , Lipopolissacarídeos/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Fagocitose/efeitos dos fármacos , Pletismografia Total , Sistema Respiratório/efeitos dos fármacos , Fator de Necrose Tumoral alfa/biossíntese , Proteínas Quinases p38 Ativadas por MitógenoRESUMO
Phosphodiesterase 4 (PDE4) is a member of the growing family cyclic AMP and cyclic GMP. Earliest described inhibitors of PDE4, such as rolipram, demonstrate marked anti-inflammatory and bronchodilatory effects in vitro and in vivo. The clinical utility of these earlier compounds was limited by their propensity to elicit gastrointestinal side effects. This has led to an extensive effort to identify novel PDE4 inhibitors that maintain the anti-inflammatory activity and bronchodilatory activity of rolipram but with a reduced potential to produce side effects. This article summarizes the evidence supporting the utility of selective PDE4 inhibitors in the treatment of asthma and chronic obstructive pulmonary disease, discusses the recent results obtained in clinical trials with second-generation inhibitors, and presents two approaches designed to identify additional novel selective PDE4 inhibitors.
Assuntos
3',5'-AMP Cíclico Fosfodiesterases/antagonistas & inibidores , Hipertensão Pulmonar/tratamento farmacológico , Pneumopatias Obstrutivas/tratamento farmacológico , Inibidores de Fosfodiesterase/uso terapêutico , Obstrução das Vias Respiratórias/enzimologia , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4 , Humanos , Hipertensão Pulmonar/fisiopatologia , Pneumopatias Obstrutivas/fisiopatologia , Estrutura Molecular , Inibidores de Fosfodiesterase/químicaRESUMO
In this study, the activity of the delta-opioid receptor subtype-selective agonist, SB 227122, was investigated in a guinea pig model of citric acid-induced cough. Parenteral administration of selective agonists of the delta-opioid receptor (SB 227122), mu-opioid receptor (codeine and hydrocodone), and kappa-opioid receptor (BRL 52974) produced dose-related inhibition of citric acid-induced cough with ED(50) values of 7.3, 5.2, 5.1, and 5.3 mg/kg, respectively. The nonselective opioid receptor antagonist, naloxone (3 mg/kg, i.m.), attenuated the antitussive effects of codeine or SB 227122, indicating that the antitussive activity of both compounds is opioid receptor-mediated. The delta-receptor antagonist, SB 244525 (10 mg/kg, i.p.), inhibited the antitussive effect of SB 227122 (20 mg/kg, i.p.). In contrast, combined pretreatment with beta-funaltrexamine (mu-receptor antagonist; 20 mg/kg, s.c.) and norbinaltorphimine (kappa-receptor antagonist; 20 mg/kg, s.c.), at doses that inhibited the antitussive activity of mu- and kappa-receptor agonists, respectively, was without effect on the antitussive response of SB 227122 (20 mg/kg, i.p.). The sigma-receptor antagonist rimcazole (3 mg/kg, i.p.) inhibited the antitussive effect of dextromethorphan (30 mg/kg, i.p.), a sigma-receptor agonist, but not that of SB 227122. These studies provide compelling evidence that the antitussive effects of SB 227122 in this guinea pig cough model are mediated by agonist activity at the delta-opioid receptor.